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IntroductionAllopregnanolone is an endogenous neurosteroid with the potential to be a novel regenerative therapeutic for Alzheimer's disease (AD). Foundations of mechanistic understanding and well-established preclinical safety efficacy make it a viable candidate.MethodsA randomized, double-blinded, placebo-controlled, single and multiple ascending dose trial was conducted. Intravenous allopregnanolone or placebo was administered once-per-week for 12 weeks with a 1-month follow-up. Participants with early AD (mild cognitive impairment due to AD or mild AD), a Mini-Mental State Examination score of 20-26 inclusive, and age ≥55 years were randomized (6:2 to three allopregnanolone dosing cohorts or one placebo cohort). Primary endpoint was safety and tolerability. Secondary endpoints included pharmacokinetic (PK) parameters and maximally tolerated dose (MTD). Exploratory endpoints included cognitive and imaging biomarkers.ResultsA total of 24 participants completed the trial. Allopregnanolone was safe and well tolerated in all study participants. No differences were observed between treatment arms in the occurrence and severity of adverse events (AE). Most common AE were mild to moderate in severity and included rash (n = 4 [22%]) and fatigue (n = 3 [17%]). A single non-serious AE, dizziness, was attributable to treatment. There was one serious AE not related to treatment. Pharmacokinetics indicated a predictable linear dose-response in plasma concentration of allopregnanolone after intravenous administration over 30 minutes. The maximum plasma concentrations for the 2 mg, 4 mg, 6 mg, and 10 mg dosages were 14.53 ng/mL (+/-7.31), 42.05 ng/mL (+/-14.55), 60.07 ng/mL (+/-12.8), and 137.48 ng/mL (+/-38.69), respectively. The MTD was established based on evidence of allopregnanolone-induced mild sedation at the highest doses; a sex difference in the threshold for sedation was observed (males 10 mg; females 14 mg). No adverse outcomes on cognition or magnetic resonance imaging-based imaging outcomes were evident.ConclusionsAllopregnanolone was well tolerated and safe across all doses in persons with early AD. Safety, MTD, and PK profiles support advancement of allopregnanolone as a regenerative therapeutic for AD to a phase 2 efficacy trial.Trial registrationClinicalTrials.gov-NCT02221622.

BackgroundData suggest that estrogen-containing hormone therapy is associated with beneficial effects with regard to cardiovascular disease when the therapy is initiated temporally close to menopause but not when it is initiated later. However, the hypothesis that the cardiovascular effects of postmenopausal hormone therapy vary with the timing of therapy initiation (the hormone-timing hypothesis) has not been tested.MethodsA total of 643 healthy postmenopausal women were stratified according to time since menopause (

ObjectiveT-cell activation is a major pathway driving HIV disease progression. Little is known regarding the impact of T-cell activation on HIV-associated atherosclerosis and cardiovascular disease, a common comorbidity in HIV infection. We hypothesized that T-cell activation will predict vascular stiffness, a measure of subclinical atherosclerosis.DesignLinear regression models evaluated the covariate-adjusted association of T-cell activation with vascular stiffness.MethodsCD38 and HLA-DR expression on CD4⁺ and CD8⁺ T cells was assessed by flow cytometry among 59 HIV-negative and 376 HIV-infected (185 hepatitis C coinfected) women in the Women's Interagency HIV Study. T-cell activation was defined by CD8⁺CD38⁺DR+ and CD4⁺CD3⁺8DR+. Multiple activation assessments over 6.5 years were averaged. In 140 women, T-cell activation was measured before and after highly active antiretroviral therapy (HAART) initiation. Carotid artery ultrasounds were completed a median of 6.5 years after last measurement of T-cell activation and carotid artery stiffness including distensibility and elasticity were calculated.ResultsPercentages of CD4⁺ and CD8⁺ T-cell activation were significantly higher in HIV- infected compared with HIV-negative women. Among HIV-negative women, T-cell activation was not associated with carotid artery stiffness. Among HIV-infected women, higher CD4⁺ T-cell activation levels significantly predicted increased arterial stiffness independent of CD4⁺ cell count and HIV RNA. The association was stronger among HIV/hepatitis C-coinfected women compared with HIV-monoinfected women; however, the difference was not statistically significant (P for interaction >0.05). Pre- and post-HAART levels of CD4⁺ T-cell activation significantly predicted carotid artery stiffness.ConclusionsPersistent T-cell activation, even after HAART initiation, can contribute to structural and/or functional vascular damage accelerating atherogenesis in HIV infection. These results need to be confirmed in a longitudinal prospective study.

BackgroundInflammation persists in treated human immunodeficiency virus (HIV) infection and may contribute to an increased risk for non-AIDS-related pathologies. We investigated the correlation of cytokine responses with changes in CD4 T-cell levels and coinfection with hepatitis C virus (HCV) during highly active antiretroviral treatment (HAART).MethodsA total of 383 participants in the Women's Interagency HIV Study (212 with HIV monoinfection, 56 with HCV monoinfection, and 115 with HIV/HCV coinfection) were studied. HIV-infected women had 200 CD4 T cells/μL; 98% were receiving HAART at baseline. Changes in CD4 T-cell count between baseline and 2-4 years later were calculated. Peripheral blood mononuclear cells (PBMCs) obtained at baseline were used to measure interleukin 1β (IL-1β), interleukin 6 (IL-6), interleukin 10 (IL-10), interleukin 12 (IL-12), and tumor necrosis factor α (TNF-α) responses to Toll-like receptor (TLR) 3 and TLR4 stimulation.ResultsUndetectable HIV RNA (

Time-resolved spontaneous and laser-induced unimolecular fragmentation of perylene cations (C20H12+) has been measured on timescales up to 2 s in a cryogenic electrostatic ion beam storage ring. We elaborate a quantitative model, which includes fragmentation in competition with radiative cooling via both vibrational and electronic (recurrent fluorescence) de-excitation. Excellent agreement with experimental results is found when sequential fragmentation of daughter ions co-stored with the parent perylene ions is included in the model. Based on the comparison of the model to experiment, we constrain the oscillator strength of the D1 → D0 emissive electronic transition in perylene (fRF = 0.055 ± 0.011), as well as the absolute absorption cross section of the D5 ← D0 excitation transition (σabs > 670 Mb). The former transition is responsible for the laser-induced and recurrent fluorescence of perylene, and the latter is the most prominent in the absorption spectrum. The vibrational cooling rate is found to be consistent with the simple harmonic cascade approximation. Quantitative experimental benchmarks of unimolecular processes in polycyclic aromatic hydrocarbon ions like perylene are important for refining astrochemical models. [ABSTRACT FROM AUTHOR]

We have measured recurrent fluorescence (RF) cooling rates of internally hot tetracene cations, C18H12+, as functions of their storage times and internal energies in two different electrostatic ion-beam storage rings – the cryogenic ring DESIREE with a circumference of 8.6 meters in Stockholm and the much smaller room temperature ring Mini-Ring in Lyon, which has a circumference of 0.71 meters. The RF rates were measured to be as high as 150 to 1000 s−1 for internal energies in the 7 to 9.4 eV energy range, where we have probed the time evolution of the internal energy distribution with nanosecond laser pulses with a 1 kHz repetition rate. These RF rates are found to be significantly higher than those of previously investigated smaller PAHs such as e.g. anthracene and naphthalene, for which the lowest non-forbidden electronic excited state, the D2 state, is populated with a smaller probability by inverse internal conversion. Furthermore, the D2–D0 transition rate is smaller for these smaller molecules than for tetracene. The complementary features of the two storage rings allow for RF rate measurements in a broader internal energy range than has been possible before. The smaller sampling period of about 6 μs in Mini-Ring is ideal to study the cooling dynamics of the hotter ions that decay fast, whereas DESIREE with a sampling period of about 60 μs is better suited to study the colder ions that decay on longer timescales ranging up to hundreds of milliseconds. The excellent agreement between the two series of measurements in the region where they overlap demonstrates the complementarity of the two electrostatic ion-beam storage rings. [ABSTRACT FROM AUTHOR]

Introduction: Study inclusion criteria and recruitment practices limit the generalizability of randomized‐controlled trial (RCT) results. Statistical modeling could enhance generalizability of outcomes. To illustrate this, the cognition–depression relationship was assessed with and without adjustment relative to the target population of older women. Methods: Randomized participants from four RCTs and non‐randomized participants from two cohorts were included in this study. Prediction models estimated probability of being randomized into trials from target populations. These probabilities were used for inverse odds weighting relative to target populations. Weighted linear regression was used to assess the depression–cognition relationship. Results: There was no depression–cognition relationship in the combined randomized sample. After applying weights relative to a representative cohort, negative relationships were observed. After applying weights relative to a non‐representative cohort, bias of estimates increased. Discussion: Quantitative approaches to transportability using representative samples may explain the absence of a‐priori established relationships in RCTs. [ABSTRACT FROM AUTHOR]

Objectives: Although carotid artery intima media thickness (CIMT) is a widely used determinant of subclinical atherosclerosis, gray‐scale median of the intima‐media complex (IM‐GSM) of the common carotid artery is a relatively novel measure of echogenicity reflecting composition of the arterial wall. It is important to compare cardiovascular disease (CVD) risk factor correlates across CIMT and IM‐GSM to determine whether these measures reflect distinct aspects of atherosclerosis. Methods: Baseline information from a completed randomized clinical trial of 643 healthy postmenopausal women without clinically apparent CVD was included in this cross‐sectional study. The women were on average ± SD 61 ± 7 years old, and predominantly non‐Hispanic White. CIMT and IM‐GSM were measured by high‐resolution B‐mode ultrasonogram in the far wall of the right common carotid artery. CVD risk factors including age, race, body mass index (BMI), smoking, weekly hours of physical activity, systolic (SBP) and diastolic blood pressure (DBP), lipids, glucose, and inflammatory markers were measured at baseline. Linear regression models were used to assess associations of CVD risk factors with CIMT and IM‐GSM. Multivariable models included groups of risk factors added one at a time with and withoutbasic demographic factors (age, race, BMI, physical activity) with model R2 values compared between CIMT and IM‐GSM. Results: In multivariable analysis, age, Black race, BMI, SBP, and DBP were associated with CIMT (all P <.05), whereas age, Hispanic race, BMI, SBP, physical activity, LDL‐cholesterol, and leptin were correlates of IM‐GSM (all P <.05). Adjusted for age, race, BMI, and physical activity, the R2 value for SBP was greater for CIMT association, whereas R2 values for lipids, glucose, inflammatory markers, and adipokines were greater for IM‐GSM associations. Conclusions: CIMT and IM‐GSM assess different attributes of subclinical atherosclerosis. Integrating both measures may provide improved assessment of atherosclerosis in asymptomatic individuals. [ABSTRACT FROM AUTHOR]

Objective  To examine the association of vitamin D insufficiency and risk of pregnancy-induced hypertension (PIH) among human immunodeficiency virus (HIV)-infected pregnant women. Study Design  This is a retrospective cohort study evaluating the impact of low maternal vitamin D levels on PIH and perinatal outcomes among HIV-infected pregnant women receiving care at an urban HIV center from 1991 to 2014. Results  A total of 366 pregnant women were included, of which 11% developed PIH. Lower levels of 25-hydroxyvitamin D (25(OH)D) and bioactive 1,25-dihydroxyvitamin D (1,25(OH) 2 D) were associated with increased HIV disease activity. 25(OH)D levels were not significantly associated with the incidence of PIH. Higher 1,25(OH) 2 D levels were associated with reduced incidence of PIH in univariate (odds ratio, OR: 0.87 [95% confidence interval, CI: 0.79–0.95], p  = 0.004) and multivariate (OR: 0.88 [95% CI: 0.80–0.97], p  = 0.010) analyses. No association was found between 25(OH)D levels and other obstetric outcomes. Lower 1,25(OH) 2 D levels were associated with group B Streptococcus colonization (OR: 0.92 [95% CI: 0.86–0.99]) and low birth weight (LBW) (OR: 0.90 [95% CI: 0.83–0.98]) on multivariate analysis. Mean 1,25(OH) 2 D levels were significantly lower in women with preterm delivery and LBW infants. Conclusion  Lower bioactive vitamin D levels are related to PIH in HIV-infected women. This association may be related to the coexistence of abnormal placental vitamin D metabolism and abnormal placental implantation. [ABSTRACT FROM AUTHOR]

Background Global immune activation and HLA alleles are each associated with the pathogenesis of human immunodeficiency virus (HIV) and hepatitis C virus. Methods We evaluated the relationship between 44 HLA class I and 28 class II alleles and percentages of activated CD8 (CD8+CD38+DR+) and CD4 (CD4+CD38+DR+) T cells in 586 women who were naive to highly active antiretroviral therapy. We used linear generalized estimating equation regression models, adjusting for race/ethnicity, age, HIV load, and hepatitis C virus infection and controlling for multiplicity using a false discovery rate threshold of 0.10. Results Ten HLA alleles were associated with CD8 and/or CD4 T-cell activation. Lower percentages of activated CD8 and/or CD4 T cells were associated with protective alleles B*57:03 (CD8 T cells, −6.6% [ P =.002]; CD4 T cells, −2.7% [ P =.007]), C*18:01 (CD8 T cells, −6.6%; P <.0008) and DRB1*13:01 (CD4 T cells, −2.7%; P <.0004), and higher percentages were found with B*18:01 (CD8 T cells, 6.2%; P <.0003), a detrimental allele. Other alleles/allele groups associated with activation included C*12:03, group DQA1*01:00, DQB1*03:01, DQB1*03:02, DQB1*06:02, and DQB1*06:03. Conclusion These findings suggest that a person's HLA type may play a role in modulating T-cell activation independent of viral load and sheds light on the relationship between HLA, T-cell activation, immune control, and HIV pathogenesis. [ABSTRACT FROM AUTHOR]